| 1 | @c Copyright 2005, 2008 |
| 2 | @c Free Software Foundation, Inc. |
| 3 | @c This is part of the GAS manual. |
| 4 | @c For copying conditions, see the file as.texinfo. |
| 5 | @ifset GENERIC |
| 6 | @page |
| 7 | @node M32C-Dependent |
| 8 | @chapter M32C Dependent Features |
| 9 | @end ifset |
| 10 | @ifclear GENERIC |
| 11 | @node Machine Dependencies |
| 12 | @chapter M32C Dependent Features |
| 13 | @end ifclear |
| 14 | |
| 15 | @cindex M32C support |
| 16 | |
| 17 | @code{@value{AS}} can assemble code for several different members of |
| 18 | the Renesas M32C family. Normally the default is to assemble code for |
| 19 | the M16C microprocessor. The @code{-m32c} option may be used to |
| 20 | change the default to the M32C microprocessor. |
| 21 | |
| 22 | @menu |
| 23 | * M32C-Opts:: M32C Options |
| 24 | * M32C-Syntax:: M32C Syntax |
| 25 | @end menu |
| 26 | |
| 27 | @node M32C-Opts |
| 28 | @section M32C Options |
| 29 | |
| 30 | @cindex options, M32C |
| 31 | @cindex M32C options |
| 32 | |
| 33 | The Renesas M32C version of @code{@value{AS}} has these |
| 34 | machine-dependent options: |
| 35 | |
| 36 | @table @code |
| 37 | @item -m32c |
| 38 | @cindex @samp{-m32c} option, M32C |
| 39 | @cindex architecture options, M32C |
| 40 | @cindex M32C architecture option |
| 41 | Assemble M32C instructions. |
| 42 | |
| 43 | @item -m16c |
| 44 | @cindex @samp{-m16c} option, M16C |
| 45 | @cindex architecture options, M16C |
| 46 | @cindex M16C architecture option |
| 47 | Assemble M16C instructions (default). |
| 48 | |
| 49 | @item -relax |
| 50 | Enable support for link-time relaxations. |
| 51 | |
| 52 | @item -h-tick-hex |
| 53 | Support H'00 style hex constants in addition to 0x00 style. |
| 54 | |
| 55 | |
| 56 | @end table |
| 57 | |
| 58 | @node M32C-Syntax |
| 59 | @section M32C Syntax |
| 60 | @menu |
| 61 | * M32C-Modifiers:: Symbolic Operand Modifiers |
| 62 | * M32C-Chars:: Special Characters |
| 63 | @end menu |
| 64 | |
| 65 | @node M32C-Modifiers |
| 66 | @subsection Symbolic Operand Modifiers |
| 67 | |
| 68 | @cindex M32C modifiers |
| 69 | @cindex modifiers, M32C |
| 70 | |
| 71 | The assembler supports several modifiers when using symbol addresses |
| 72 | in M32C instruction operands. The general syntax is the following: |
| 73 | |
| 74 | @smallexample |
| 75 | %modifier(symbol) |
| 76 | @end smallexample |
| 77 | |
| 78 | @table @code |
| 79 | @cindex symbol modifiers |
| 80 | |
| 81 | @item %dsp8 |
| 82 | @itemx %dsp16 |
| 83 | |
| 84 | These modifiers override the assembler's assumptions about how big a |
| 85 | symbol's address is. Normally, when it sees an operand like |
| 86 | @samp{sym[a0]} it assumes @samp{sym} may require the widest |
| 87 | displacement field (16 bits for @samp{-m16c}, 24 bits for |
| 88 | @samp{-m32c}). These modifiers tell it to assume the address will fit |
| 89 | in an 8 or 16 bit (respectively) unsigned displacement. Note that, of |
| 90 | course, if it doesn't actually fit you will get linker errors. Example: |
| 91 | |
| 92 | @smallexample |
| 93 | mov.w %dsp8(sym)[a0],r1 |
| 94 | mov.b #0,%dsp8(sym)[a0] |
| 95 | @end smallexample |
| 96 | |
| 97 | @item %hi8 |
| 98 | |
| 99 | This modifier allows you to load bits 16 through 23 of a 24 bit |
| 100 | address into an 8 bit register. This is useful with, for example, the |
| 101 | M16C @samp{smovf} instruction, which expects a 20 bit address in |
| 102 | @samp{r1h} and @samp{a0}. Example: |
| 103 | |
| 104 | @smallexample |
| 105 | mov.b #%hi8(sym),r1h |
| 106 | mov.w #%lo16(sym),a0 |
| 107 | smovf.b |
| 108 | @end smallexample |
| 109 | |
| 110 | @item %lo16 |
| 111 | |
| 112 | Likewise, this modifier allows you to load bits 0 through 15 of a 24 |
| 113 | bit address into a 16 bit register. |
| 114 | |
| 115 | @item %hi16 |
| 116 | |
| 117 | This modifier allows you to load bits 16 through 31 of a 32 bit |
| 118 | address into a 16 bit register. While the M32C family only has 24 |
| 119 | bits of address space, it does support addresses in pairs of 16 bit |
| 120 | registers (like @samp{a1a0} for the @samp{lde} instruction). This |
| 121 | modifier is for loading the upper half in such cases. Example: |
| 122 | |
| 123 | @smallexample |
| 124 | mov.w #%hi16(sym),a1 |
| 125 | mov.w #%lo16(sym),a0 |
| 126 | @dots{} |
| 127 | lde.w [a1a0],r1 |
| 128 | @end smallexample |
| 129 | |
| 130 | @end table |
| 131 | |
| 132 | @node M32C-Chars |
| 133 | @subsection Special Characters |
| 134 | |
| 135 | @cindex line comment character, M32C |
| 136 | @cindex M32C line comment character |
| 137 | The presence of a @samp{;} character on a line indicates the start of |
| 138 | a comment that extends to the end of that line. |
| 139 | |
| 140 | If a @samp{#} appears as the first character of a line, the whole line |
| 141 | is treated as a comment, but in this case the line can also be a |
| 142 | logical line number directive (@pxref{Comments}) or a |
| 143 | preprocessor control command (@pxref{Preprocessing}). |
| 144 | |
| 145 | @cindex line separator, M32C |
| 146 | @cindex statement separator, M32C |
| 147 | @cindex M32C line separator |
| 148 | The @samp{|} character can be used to separate statements on the same |
| 149 | line. |